The present invention relates to a storage system and obstacle elimination method for the storage system.
A storage system comprises one or more storage devices that are used by a plurality of host computers (servers or similar), for example. Respective host computers and storage devices are connected via a relay device such as a fiber channel switch, hub, or the like.
A storage device can also be called a disk array device or the like, for example, and is constituted by arranging a multiplicity of disk drives in the form of an array. Storage devices provide a RAID (Redundant Array of Independent Inexpensive Disks)-based storage area, for example. A logical volume (logical device), which is a logical storage area, is formed on a physical storage area that each disk drive comprises. Further, a host computer such as a server issues write commands or read commands of a predetermined format to the storage device, whereby the reading/writing of the desired data can be executed.
Each host computer accesses an allocated logical volume via a predetermined path to read/write data. The system administrator or similar is able to allocate the logical volume by considering the load uniformity distribution. A technology that allocates the lowest-load logical volume to the host computer that has been newly added to the storage system is also known (Japanese Patent KOKAO Publication No. H10-320126).
A technology is also known according to which a plurality of communication paths is set beforehand, and, when a power supply fault or similar occurs, data is transferred via a bypass (Patent KOHYO Publication No. 2004-503956).